TOKYO—Buoyed by a five-fold surge in net income in the fiscal fourth quarter and a return to full production capacity, an upbeat Toyota Motor Corp. on Wedneday forecast a doubling of profits in the current fiscal year through March 2013.

Japan’s largest car maker by volume recorded a net profit of ¥121.0 billion ($1.51 billion) in the three months ended March, up from ¥25.4 billion a year earlier, marking the first quarterly growth in six quarters. The result beat analysts’ estimates for ¥112.9 billion net profit in a poll compiled by data provider FactSet.

The company sees its net profit more than doubling to ¥760 billion in the current fiscal year through March. In the just-ended fiscal year, Toyota’s net profit dropped 30.5% to ¥283.56 billion. Sales for this fiscal year are seen rising 18.4% to ¥22.000 trillion, while operating profit is expected to nearly triple to ¥1.000 trillion.

The upbeat outlook comes after a series of difficult challenges for Toyota over the last few years, including high-profile quality-control issues and natural disasters at home and abroad. The Japanese company ceded the title of world’s biggest auto maker to General Motors Co. last year.

“In recent years, we have suffered periods of hardship,” said Toyota President Akio Toyoda at a press conference. “This year, I am determined to show tangible results of all our internal efforts,”

The outlook for the fiscal year is based on the assumption the dollar will average ¥80 and the euro ¥105 during the period, compared with ¥79 and ¥109 in the previous 12 months.

The marginally higher dollar rate for this fiscal year will slightly ease the pressure of the strong yen on its bottom line.

But with the car maker in the midst of drive to increase exports from Japan to make up for lost production last year, Toyota Chief Financial Officer Satoshi Ozawa warned that sensitivity to any fluctuations in the dollar will rise this fiscal year.

Each weakening of the dollar by one yen, will cut the company’s operating profit by ¥35 billion this fiscal year, larger than ¥32 billion in the last fiscal year, he said.

Toyota joins Honda Motor Co. in projecting a substantial turnaround in the current fiscal year, underscoring how Japan’s auto industry aims to win back customers lost to U.S., German and South Korean rivals.

Honda, Japan’s third biggest car maker by volume, in late April reported a 61% jump in net profit and said it expects its net profit to more than double to ¥470 billion for this fiscal year.

Analysts expect Nissan Motor Co. to join its two major local rivals in forecasting a bright profit outlook when it releases January-March results and its projection for the year on Friday.